Many commercial air filtration devices currently available employ an air blowing means, such as a fan, and position filters and filter media of various kinds either upstream or downstream of the air blowing means, or both. It is also known to provide a chamber in the downstream air flow, which is filled with a scented liquid so that the air leaving the device is given a particular aroma.
However, many of the prior art devices have disadvantages which arise from a lack of symmetry in the construction, and additionally fail to entrain a large enough portion of the air in a room. It is in view of the above two disadvantages that the present structure has been devised.